Tuesday afternoon, a few honeybees still buzzed around a tree outside Smiles by Design in Hortonville. Monday, the scene was much different.

"It was a swarm of bees, it looked like a black cloud. It was enormous! It was crazy!" exclaimed employee Amy Thorp.

Thorp noticed the buggers first, but didn't really know what she was seeing.

"I started getting photos!" she said, laughing.

In those photos you can see thousands of bees grouped together in the tree.

"Where are they coming from and where are they headed? Because they seemed to swarm right outside my work window for awhile," Thorp explained.

A similar situation happened in Fond du Lac over the weekend.

According to the DNR, honey bees often swarm when their hive or colony becomes over-crowded. Thousands of them will fly to a new place and swarm there to rest and protect the queen. During that time, scout bees will leave and look for a new place to build a new colony. The Fond du Lac Fire Department told us when honeybees swarm they usually leave after a few days. However, beekeepers will often remove the bees if they're in well-populated areas.

The DNR does say the insects aren't usually aggressive during swarms, but Thorp told FOX 11 she was wary of possible stings.

"Initially, yes, and then I found out they were swarming to protect a queen bee," she said.

In Hortonville and Fond du Lac, experts relocated the bees.

"We had some bee keepers that came and shook the branches to try and remove the queen," Thorp explained, saying it took two days to remove most of the insects.

When experts relocate the bees, the goal is to keep them safe. Honey bees are dying out at unusually high rates thanks to something called colony collapse disorder.

It's unclear what causes the disorder, the USDA has said many causes from pesticides to parasites to viruses could be to blame.

According to the USDA, honey bees are key in pollinating crops, saying about one in three mouthfuls of the food we eat is thanks to the insects.

"We wanna keep them. So when the bee keepers came in, it was very interesting, it was cool," remarked Thorp.